Ill. Admin. Code tit. 92, § 3280.1030 – Subpoenas

a) The presiding officer, designated to preside over a hearing convened in accordance with Section 386.1150(b), shall issue subpoenas on his own initiative, or upon the request of any person participating in that proceeding. The presiding officer shall issue subpoenas on his own initiative when the presiding officer believes that the production of relevant documents or the appearance of a particular witness shall materially advance the proceeding and those documents or witnesses have not been subpoenaed by any other party to the proceeding. (Section 18b-102(b) of the Law)
b) A subpoena may require the attendance of a witness, or the production of relevant documentary or other tangible evidence in the possession or under the control of the person served, or both.
c) Service of a subpoena upon the person named therein shall be made by:
1. 1) delivering a copy of the subpoena to such person;
2. 2) delivering a copy of a subpoena to a natural person by handing it to that person, leaving it at his or her office with the person in charge, leaving it at his dwelling place or usual place of abode with some competent adult person of legal age who resides therein; or
3. 3) mailing it by certified mail to the person at the person's last known address.
d) When the person to be served is not a natural person, delivery of a copy of the subpoena shall be effected by:
1. 1) handing it to a registered agent for service, or to any officer, director, or agent in charge of any office of the person; or
2. 2) mailing it by certified mail to that representative at his last known address.
e) The original subpoena bearing a certificate of service shall be filed with the Department official having responsibility for the proceeding in connection with which the subpoena was issued.
f) Any person to whom a subpoena is directed may, prior to the time specified therein for compliance, but in no event more than 10 days after the date of service of such subpoena, send a written request to the presiding officer who issued the subpoena, to quash or modify the subpoena. The written request shall contain a brief statement of the reasons relied upon in support of the action sought therein. The presiding officer (as designated under Section 386.1160(a)) shall:
1. 1) deny the written request;
2. 2) quash or modify the subpoena if it is unreasonable, immaterial, irrelevant, or to prevent delay, expense, harassment or oppression; or
3. 3) condition denial of the written request to quash or modify the subpoena upon the satisfaction of certain just and reasonable requirements to avoid delay, expense, harassment or oppression. The denial may be summary.
g) If there is a refusal to obey a subpoena served upon any person under the provisions of this Section, the Department may request the Attorney General to seek the aid of the Circuit Court or any court of competent jurisdiction in which the person is found, to compel that person, after notice, to appear and give testimony, or to appear and produce the subpoenaed documents before the Department, or both.
(Recodified from 92 Ill. Adm. Code 386 (Department of Transportation) pursuant to P.A. 104-0025, at 49 Ill. Reg. 12543)